Feeding mechanism for sewing machines



Jun; 9, 1925. 1,540,778

M. HEMLEB FEEDING MECHANISM FOR SEWING MACHINES Filed July 16, 1923 2 Sheets-Sheet 1 INVENTOR wl'mss gss Y 7 ATTORNEY June 9, 1925.

Filed July 16, 1923 2 Sheets-Shut 2 TTORNEY Patented June 9, 1925.

UNITED STATES i 1,540,778 PA p0 MARTIN HEMLEB, or ELIZABETH, NEW JERSEY, Assisno'n fro ,TI-IE, srivenn Menu racrunnve COMJEANY, or ELIZABETH, NEW JERSEY, a oonronerro'n or vnvv J ERSEY.

FEEDING MECHANISM roe SEWING Maomnns; I

Application filed July 16, 1923. Serial No. 65 1,801.

To all whomit may concern:

Be it known that -MARTIN HEMLEB, a

citizen of the United States, residing at Elizabeth, in the county of Union and State of New Jersey, has invented certain new and useful Improvements-in Feeding Mech anisms for Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings;

This inventionrelates to feedingmechanism for sewing machines and has for an object to improve the feedi'ngmechanism disclosed in the patents to Willcox, No. 572,039 and No. 572,041, both of November 24, 1896, by overcoming the tendency of the adjustable feed-advancing eccentric to chat ter at high speeds and cramp within the eccentric strap at the upper end of the pit-' man which embraces it. V

By referring to Fig. 2 of the Wi1lcox Patent No. 572,041, it will be a pr ciated that at the reversal,'say,fromup to; down motion of the feed-advancing 'pitman Q, a reaction strain is imposed uponthe eccentric E whichtends to rock the eccentric and its carrier-plate about theupper portion of the edge of the central or adjusting plate F as a fulcrum, thereby moving the lower portion of theeccentric carrier-plate away from the adjusting plate F and compressing the lower spring 6 until arrested by the head of the'adja'cent screw 6. In the recovery of the parts at a later stage,

the lower spring 6 returns the adjacent por-.

-. tion of-the eccentric carrier-plate into contact relation with theadjusting plate F. Rapid repetition of these forcestends to produce chattering of the the eccentric'E in its strap. 7

According to the" present improvement each of the holding screw-pins is provided under its head with a stiff washer-of a thickness sufficient to fill the space between the head of the screw-pin and the eccentric carrier-plate, soas to positively hold the: carrier-plate against rocking or cramping movement and at all times with its axis parallel tothe shaft axis. Internal spring disks are provided to exert the desired fric-' tional drag uponthe central. adjusting plate.

Another'feature of the present improvement consists in arranging the feed-lifting and feed-advancing eccentrics on opposite sidesof the feed-adjusting disk, the. feedlifting eccentric being formed on themain parts and cramps;

. supporting disk "of the feed-adjusting means, thereby simplifyingthe priorconstruction above referred to, reducing the space required on the'main-shaft for-the feed connections, and giving more room for downwardly alongside'the feeding connections within the hollow vertical frame member of the machine.

In'the accompanying drawings, Fig. '1 is a transverse vertical section on the line 1 1,- Fig. 6, through the sewing'machinemainshaft and standard, showing the feeding mechanism in elevation. Fig. 2 is" a sec-' tional View of the feed-adjusting means. Fig. 3 is an inner face view of the mainsupporting disk for the feed-adjusting means. Fig. 4- is a face view'of the intermediate orfeed-adjusting disk. Fig. 5 is an inner faceview 'ofthe carrier disk for the feed-advancing eccentric. Fig. 6 'is a horizontal section through the sewing machine gooseneck, showing the main-shaft and feeding cams intop' plan; Fig. 7 is a; sec tionon the line 7 7, Fig. 6, and Figs-.8

views :of one in Fig. 2. j l a j 1n the preferred embodiment of-the in vention, as illustrated, 1 represents the hollow vertical mem'ber a-nd 2the horizontal member of a. sewing machine gooseneck within which latter is journaled the mainshaft -3 carrying on its outboard projec v tion the usual balance-wheelie Mounted on the main-shaft 3, within the' hollow frame member or gooseneckyis thje drivinggean 5 which meshes with the driven gear 6 on'the vertical shaft 7 extending downwardly with in-the vertical member 1' of gooseneckand at its lower endconnected in the; usual man ner to drive the loop-takerlor rotary'hook shaft." I The feeding mechanism preferably jco'mof the spring washers shown prises the feed-dog'8 carried by'the feed- 100 bar 9 which is pivoted at 10 to thefee'd rocker arm 11 supported by the usual'fee'd advancing rock-shaft 12. The feed-advancing rook-shaft is actuated bymeans ofthe eccentric 13 which is connected by means 1 arm" 15 fast on the strut 16 having at its upper end"a*ball-' en 7 the hook driving conneotions which extend L and 9 are, respectively, face and sectional and-socket connection 17 with the feed-bar 9 and at its lower end a. ball-and-sockct connection 18 with the horizontal arm 19 of an L-shaped arm, the vertical member 20 of which is fast on the feed-lifting rock-shaft 21. The rock-shaft 21is actuated by means of the eccentric 22 on the main-shaft :2;

said eccentric being; connected by means of the pitman 23 to an arm 2 fast on the rockshaft 21.

Referring more particularly to Figs. 2 and 3, it will be seen that the feed-lift eccentric 22- is integral with the main-supporting disk of the feed adjusting mechanism to be described. The disk 25 is fixed. upon the main-shaft 2 by means of the quartered set-screws 26 and isprovided in its inner face with i shallow circular recesses 27 for four dished spring washers 28; each of the spring washers being preferably split radially as at 29, Fig. 8.

Fitted to turn freely on the hub 30 of the carrier-disk 25 is thefeed-adjusting disk 31 having the diametrically opposed peripheral notches 32, the concentric clearance slots 33 for the screw-pins 34, and the eccentric slots 35. Lying; adjacent the adjusting disk 31 is the carrier-disk 36 integral with the feedadvancing eccentric 13. The disk 36 is formed; with the radial guide-slots 37 which embrace the screw-pins 34; and confine the eccentric 1-3 to move radially of the axis of" the main shaft 2 during its adjustment on the main-supporting disk 25.. The disk 36 carries a pin 38 on which is journaled a roller 39 entering one of the eccentric slots on the adjusting disk 31. The screW- pins 3d are shouldered at 40' and are pro vided; under their heads with stiff washers 41; which latter plus the disks 31 and 36 completely fill the space between the screwheads, and the main-supporting disk 25- without binding; or gripping the: adjusting disk 31;. The, spring washers 28 impose the requisite constant frictional drag upon the adjusting disk 31 to 'preve-nt shift of the latter; under operating conditions.

It Will observed that the axisof the eccentric; 13- is confined to parallelism with: thic axis of; the main shaft; The disk is confined to parallelism with the Irwin-supporting dish 25 and. there is no possibility of tilting of the disk 36 even nde the heavy alternating stresses i-mposed by high-speed operation.- As a result.

quiet; ope ation and freedom from chatterassureda Orampingof the eccentric 1a it t a ii a alsooverccme,

12 Orderto mount the disk: 25 on the: shaft 3 with: the2 requisite, rigidity and freedean 'fromit tii g tendency such diskshould preferably be formed with a hiub' and by utilizing snchhub for a feed lift eccentric i a, inimum of space longitudinally of. the:

mainh m i reeuiredend ample: room: res

sides of the adjusting mechanism.

The wall of the'gooseneck is apertured at 42 to receive the bushing support 13 for the spring returned push-pin 4 1 which is adapted to enter one of the notches 32 in the feed adjusting disk 31. When it is desired to adjustthe feed, the operator pushes upon the pin 441- and rotates the main-shaft by turning the balance-wheel 4-, until the pin 44 enters one of the notches 32 and locks the adjusting disk 31. By further turning the balance-wheel 1, thedisks 25 and 36 are rotated relative to the adjusting disk 31 and the roller 39 is caused to travel along one of the eccentric slots 35, thus shifting the disk 36 and the feed-advancing eccentrio 13 radially of the main-supporting disk 25 and altering the eccentricity of the cccentric 13. To assist in securing the desired feed adjustment; the balance-wheel may be graduated in stitches per inch, as shown in Fig. 7, and a pointer or indicator &5 mounted on the machine frame. By turning the balance-wheel until the desired number appears in the slot ,in the indicator, the machine will be set to sew that number of stitches per inch.

Having thus set forth the nature of. the invention,,what I' claim herein is:

1. Feeding mechanism for sewing machines comprising a main-shaft, a main sup porting disk fast on said main-shaft, and

having a hub constituting a feed-lifting eccentric, a. carrier-disk adjustable relative to said main-supporting disk, a feed-advancing eccentric formed integral with said carrierdisk, an adjusting cliskintermediate said main and carrier disks, a feed dog, and operative connection between said eccentrics and saidfeed-dog.

2. Feeding mechanism forsewing machines comprising a main-shaft, a'main' supporting disk fast on'said shaft, a feed-adjusting disk adjacent said main supporting disk,; a carrier disk disposed adjacent: said feed-adjusting disk and adjustable tovary tively, by said main and carrier elements, a

feed-dog, and operative connections between said eccentrics and said feed-dog.

4. Feed adjusting mechanismfor sewing machines comprising a shaft, a main supporting disk fast on said shaft, a feed eccentric'carrier disk mounted to slide radially of said main-supporting disk, an adjusting disk intermediate the main-supporting and feed-eccentric carrier-disks, rigid holding means engaging said carrier-disk for unyieldingly confining the latter to parallelism with the main supporting disk, and yielding means for imposing a frictional drag upon the adjusting disk.

5. Feed adjusting mechanism for sewing machines comprising a shaft, a'main supporting disk fast on said shaft, a feed eccentric carrier-disk mounted to slide radially of said main supporting disk, an adjusting disk intermediate the main-supporting and feed-eccentric carrier-disks, rigid holding means engaging said carrier disk for unyieldingly confining the latter in parallelism with the main. supporting disk, and yielding means intermediate the main-supporting and adjusting disks and spaced from said holding means for imposingka frictional drag upon the adjusting dis 6. Feed adjusting mechanism for sewing machines comprising a shaft, a main supporting disk fast on said shaft, a feed eccentrio carrier-disk mounted to slide radially of said main-supporting disk, an adjusting disk intermediate the main-supporting and feed-eccentric carrier-disks, rigid holding means engaging said carrier-disk for un-.

yieldingly confiningthe latter to parallelism MARTIN HEMLEB. 

